The Beatles didn’t officially break up until 1970, but the band was already beginning to rupture internally before that. In 1969, George Harrison temporarily left The Beatles and wrote a song that captured his frustrations with his fellow bandmates. He did return to the band, but not before airing out his grievances.
George Harrison briefly left The Beatles during the ‘Let it Be’ sessions

In 1969, The Beatles were recording what would be their final album, Let it Be. The recording sessions were captured in the 1970 documentary of the same name, and footage showed high tensions between the band. While Paul McCartney and John Lennon had always been the main songwriters for the band, Harrison had long felt ignored and reached his breaking point while the band was recording the track “Two of Us.”